Help ID a McCormick Deering Power Unit

I have a McCormick Deering power unit that belonged to my late father and grandfather. They purchased it in the mid-50's and it powered their sawmill for ten years or so. It was disassembled in the late 60's to fix a valve problem. Parts were hard to obtain at the time so the unit was never ran again. A replacement valve was machined for it back in the early 80's, but was never installed. It's been under cover for the past 35 years and the head and oil pan are in a shed. My question is : What exact model is this unit? I'm thinking a P-300, but I can't find a model tag anywhere on it. The block is dated 12. 27. 35. Also, any ideas of the value of this machine? It's all there and in pretty good shape, although the bottom of the fuel tank is rusting out. It belongs to my brother and me now. We both agree that we will probably never restore it, so we would like to sell it.

Looke more like a 10-20 or W-30 engine with the oli filter at mid-length and the throttle shaft running to the front of the engine. Certainly not a 12 or 14 engine and the filter is at the back end of the side of the block and the governor unit and the spark plugs are on the other side of the engine.

Looke more like a 10-20 or W-30 engine with the oli filter at mid-length and the throttle shaft running to the front of the engine. Certainly not a 12 or 14 engine and the filter is at the back end of the side of the block and the governor unit and the spark plugs are on the other side of the engine.

The W-12 engine was sold as the P-12 power-unit The 10-20 engine was sold as the No.200 power-unit The W-30 engine was sold as the P-30 power-unit The 15-30 (22-36) engine was sold as the No.300 power-unit

Google those power-unit models numbers, there are photos of them on Wisconsin Historical Images website.

Looke more like a 10-20 or W-30 engine with the oli filter at mid-length and the throttle shaft running to the front of the engine. Certainly not a 12 or 14 engine and the filter is at the back end of the side of the block and the governor unit and the spark plugs are on the other side of the engine.

The W-12 engine was sold as the P-12 power-unitThe 10-20 engine was sold as the No.200 power-unitThe W-30 engine was sold as the P-30 power-unitThe 15-30 (22-36) engine was sold as the No.300 power-unit

Google those power-unit models numbers, there are photos of them on Wisconsin Historical Images website.

Size wise it looks like a 10-20 engine

My guess only.

M.H.

Thanks for the info guys. Looking at photos of the power units mentioned above, mine appears to be the 15-30 ,No. 300. The 10-20 (No.200) seems a bit smaller than mine according to some measurements I ran across online. Any ideas on the value of the unit? I'm not looking for an exact appraisal, just a rough estimate. Including the stand, this thing probably weighs a ton. I've had a couple of antique farm machinery guys telling me I could get more out of it in scrap than if I sold it right out! (Don't worry, I'm not going to scrap it).

They are more the "old engine" crowd rather the "old tractor" crowd it seems.

Best of luck, try various old engine clubs etc,

P.S. My notes on No.300 (a.k.a. P-300) power unit is that there were two versions.The early one was built from 1929-32The later was built 1935-41The later one, probably yours, is the same as the 22-36 ("New 15-30") tractor engine with a 4.75" bore x 6" stroke.

NEW HOME... Jim and I got together and now his power unit resides in Ohio. Amazingly, it's in good shape for being under a tree and a tarp for over thirty years. Sleeves and pistons look usable and are unstuck, so hopefully I'll get by with only needing gaskets and rings. It looks like I'm also gonna need seven new valves and an exhaust seat. Hopefully I won't have to more than double my original investment. Got it cleaned up the other day and put some wheels under it (makes it easier to handle in the shop). I don't have any plans for it, it's my first power unit, but I have a 22-36 tractor (same engine). So now I have a set I guess.
P.S. Anyone know where I can find a gas and water tank for it?